300M problems

I have a 2001 300M and never had any problems with it until recently. A few weeks ago it wouldn't start and the battery was draining. The mechanic checked alternator and battery and that wasn't the problem. He pulled fuses #7 and 19 and there was no drain and the car would start for a few days. He replaced the interior light switch and ignition switch as others suggested. The car would be okay for about 4 or 5 days and then againwon't start. Sometimes also the interior lights go off after 2-3 seconds while other times there are on the for 20-30 seconds and the manual describes them to operate.

It was working fine for a few days and then this morning my husband went to start it and it wouldn't start. He jumped it and let it run for a while. When I got in it this morning it barely started and all the cd lights were blinking for about 30 seconds. Also I haven't had a radio in about a year. I've read I got the bad radio for that year since it says RBB under the hour and minutes. Do you think the radio could have a short in it that's causing the battery drain?

Has anyone ever had a problem like this and know what it is? Our mechanic talked to a friend of his at a Chrysler dealer and even he has no idea what the problem is and suggested we bring it to a dealer.

The car is mint and only has 40,000 miles on it. I'd hate to get rid of it but I also don't want to keep putting money into it.

I'd appreciate any help of suggestions. Thanks!

Carolyn

Carolyn, the first thing I would check are both battery terminals. Our M's have a history of corrosion at the terminal and sometimes they are so bad the car won't start or the terminal actually falls apart. The battery is under the air intake box behind the passenger side headlight.

Second, I would check both jumper terminals. These are the positive and negative posts under the hood where you would attach the jumper cables. The positive is near the same air intake box I jsut mentioned and a little to the right; the negative is on the passenger side back towards the firewall/inner fender. A picture should be in your manual if you can not find them. These jumper terminals also become corroded and need to be taken apart and thoroughly cleaned (each part, including the post) with a wire brush or steel wool. Get them shiny and bright and reattach. Spray them with some battery terminal grease to protect them - you can buy this at any parts store. Use caution with the positive terminal when you take it apart. Remember the battery is still connected and if you touch that positive terminal to any metal you will have a distinct problem up to and including your battery possibly exploding.

If this does not turn out to be the answer then there are other avenues to explore, but do the simple and easy ones first.

1999 Chrysler 300m 3.5L this problem happen to me. The problem is the cable from the battery to the Alternator is cut and is shortening out. if you jump the battery the car will run until the battery is drained because the alternator is unable to recharge the battery through the cable and the alternator shortens out. all your emergency lights will come on.